Not applicable.
Not applicable.
1. Field of the Invention
This invention relates to doors made from extruded foamed plastic. More specifically, it relates to bi-fold doors or half doors made from extruded foamed plastic, such as polyvinyl chloride (PVC). The side stiles, horizontal rails, and slatted vanes that make up the door are individual solid pieces that are formed by extruding foamed plastic through a die. The invention contemplates that the door be assembled in a manner similar to that used for a conventional wooden door.
2. Description of the Related Art
Traditionally, bi-fold doors or half doors have been made of wood, but the expense of wood has caused the industry to search for other suitable materials. Recently, manufacturers have turned to fabricating such doors from synthetic resins by injection molding, as described in U.S. Pat. No. 3,985,175. However, the injection molding process is limited in its application. Typically, the injection molding process involves making two rectangular hollow pans and joining the pans together by the edges to form a hollow door. U.S. Pat. No. 3,985,175 describes a particular type of construction wherein a front face is made of injection molded plastic and has reinforcing members on the back side but no back face. Such a construction, while serving to maintain rigidity, provides a door having only one good side. Such a door is unsuited for general applications in the home or office.
One of the main problems with full length doors made from injection molded plastic is their lack of rigidity. Therefore, there is a need in the industry for a plastic door that has sufficient rigidity and is aesthetically pleasing from both sides.
Full length bi-fold and half doors may be constructed from foamed plastic, such as PVC, that is extruded to form the various pieces used to construct the door. Foamed plastic has the advantage of being as light as wood because the air within the plastic decreases the density of the plastic. More importantly, however, this type of construction material offers several advantages over wood. A foamed plastic door is much more fire resistant than wood. Furthermore, foamed plastic material does not warp from humidity. Additionally, the finished product manufactured from plastic does not require painting and is a solid color throughout so scratches from ordinary use are not readily visible. Finally, foamed plastic can be made with color variations and can be embossed with a wood grain finish so it is as aesthetically pleasing as wood.